Airplane propeller



W. D. PARKER.

AIRPLANE PHOPELLER.

APPucATloN FILED MN. 12. 192|.

W. D. PARKER.A AIHPLANE PROPELLER.

APPLlcATlou man um. 12. |921.

Patented m1241922.

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE.

WILL D. PARKER, 0F BARTLESVILLE, OKLAHOMA, ASSIGNOR OF L. STURM, 0F BARTLESVILLE, OKLAHOMA.

AIRPLAN E PROPELLER.

Specication of Letters Patent.

Patented Jan. 24, 1922.

To all whom t may concern.'

Be it known that I, WILL D. PARKER, a citizen of the United States, residing at Bartlesville, in the county of Washington and State of Oklahoma, have invented certain new and useful Improvements in Airplane Propellers, of which the following is a specification, reference being had to the accompanying drawings.

It is the purpose of the present invention to provide an airplane propeller, wherein, as the power of the engine is increased likewise increasing the peripheral speed of the motor shaft, the pitch of the propeller blades will correspondingly automatically vary, thereby causing a ma-Ximum air displacement and relatively increasing the pulling power of the blades to the engine.

Another purpose is to provide a device of this character including means for simultaneously and automatically increasing the radial length of the blades and relatively increasing the angular pitch of the blades, as the .operating means 1s increased.

Still another purpose involves an airplane propeller, wherein the blades assume a minimum angular pitch relatively to the minimum speed of the motor, so that when the power of the motor is increased, the angular pitch of the propeller blades will correspondingly increase, so as to increase the pulling power of the propeller relatively to the engine, there being means for governing such action of the propeller, according to the peripheral speed of the motor shaft.

A further purpose is to provide an airplane propeller, wherein the blades are movable axially outwardly .through-centrifugal force, in combination with means for resisting this force correspondingly to the minimum power of the motor, and maintaining the 'blades at a minimum angular pitch. As the motor shaft increases in power, the governor is actuated, thereby lessening'the resistance relatively to` the centrifugal force, allowing the propeller blades to assume different angular pitches,

`Whi le the design and construction at present illustrated and set forth is deemed preferable, it is obvious that as a result of a reduction of the invention to a more practical form for commercial purposes, the invention may be susceptible of changes. andthe right to these changes is claimed, provided they are comprehended Within the scope of what is claimed.

The invention comprises further features and combination of parts, as will be hereinafter set forth, shown in the drawings and claimed.

In the drawings Figure 1 is a. view in section of a houslng or casing, with a propeller shaftl and motor in elevation, showing parts of the pitch governing means for the propeller in elevation, showin the propeller blades in dotted lines and 1n dot and dash lines, the dotted lines representing the blade beyond the casing, while the dot and dash line represent the blade (which is not visible according to the character of view) which is to this side of the casing, and also showing the blades assuming a minimum pitch.

F'igure 2 is a similar View showing the blades assuming an increased angular pitch. Figure 3 is a, sectional view on line 3 -3 of Figure 1, more clearly showing the construction of the connections of the propeller blades, and also illustrating the interior.

slrufture of the casing carried by the motor s a A Figure 4 is an enlarged detail view of an arm which is carried by the connector of the shank of the propeller blade.

Figure 5 is a detail View of a portion of the casing or housing and showing parts `of the ring plates 17 and 18.

Referring to the drawings, 1 design a portion of a motor and 2 denotes the motor shaft, while 3 designates a housing or casing, which is rotatable with the shaft.

'The disc wall 4 of the housing has an opening 5 and provided with a hub, and through which the motor shaft extends. The motor shaft 2 has a shoulder! 6 which the casing or housing engages, The hub 7 1188 ONE-HALF TO RAY y its flange 8 secured to the disc wall of the housing or casing as at 9.

A governor body 10 is threaded upon the motor shaft in contact with one end of the hub, so as to bear against the hub and hold the casing or housing against said shoulder, whereby the governor body, the casing or housing and all other parts may rotate with the motor shaft.

This casing or housing has an angular wall 11 including an inturned flange 12, which is in parallelism with the disc Wall 4. A suitable nose plate or cover 13 is boltedor otherwise secured at 14 tothe inturned flange 12, to insure a complete housing or casing for the mechanism for changing the pitch of the propeller blades.

Fixed to the disc wall 4 of the housing or casing by the nuts 15 and correspondingly connected to the inturned flange 12 by the nuts 15a are rods 16. These rods are arranged at intervals preferably four in number, though it is obvious that any number of rods may be employed, and act as supports andv guides for the ring plates 17 and 18.-

The ring plate 18 is automatically movable and guided upon the rods 16, while the ring plate 17 is, under ordinary circumstances, stationary. The rods 16 are threaded as shown, and engaging said threads are nuts 20 and 21, which may be adjusted, for adjusting the ring plate 17 relatively to the ring plate 18.

The governor body 10 has a set bolt 22 for engaging into the hub, for holding the governor body relatively to the hub.

The nose plate 13 for the casing which carries the propeller blades may be any suitable contour, preferably as shown, or instance substantially frusto-conical sha e, and may be constructed of any suitable metal preferably cast aluminium. The extreme nose of this plate 13 has an openin 23 for the reception of the extreme end o the governor body 10, tending to steady or stabilize the entire structure.

The governor body is provided with diametrically opposite radial arms 24, to which the levers 25 are connected. One end of each of these levers 25 carries a ball 26, while its other end is connected to a link 27. This link is in turn connected to a turn buckle 28, links 29 are connected to the turn buckles, and are in turn pivotally connected at 30 to the movable ring plate 18.

The casing or housing is provided with offset extension tubes 29, which have internal spiral threads 30, which are engaged by the spiral threads 31 on the exterior of the shanks of the propeller blades 32. The shanks of the propeller blades have rectangular bores 33 in which the sliding connectors 34 engage.

The hub 7 is provided with diametrically opposite radial lugs 35, to which the rods 36 are connected, there being loosely arranged cushioning Washers 37 and the nuts 38 and v hold the rods 36 relatively to the connectors.

Arms 42 are provided, land these arms have Shanks, which pass through the connectors and are provided with nuts 43 to hold the ,arms relatively to the connectors. It will be noted that the rods 36 thread into the ends of the connectors, and are held from turning by the lock nuts 41. The arms 42 are shaped or curved not 'only as shown in Figure 3, but are also extended toward the disc wall 4 of the casingor housing, so that the extremities of the arms may engage between the ring plate 18 and the disc wall 4 of the casing or housing.

Coiled expansion springs 44 are interposed between the ring plates 17 and 18, there being lugs on the plates to hold the springs in place. Where the connectors are connected to the lugs 35 expansion coiled springs are omitted, to afford spaces of diametrically opposite portions, to make room for said connections.

The ring plate 17 is adjusted, to tension the coiled springs 44, whereby sufficient pressure of the ring plate 18 maybe exerted on the arms 42, to .hold the propeller blades 32 at a minimum angular pitch, according to thefminimum peripheral speed of the motor sha t. f

When the power of the motor is increased,

thereby relatively increasing the peripheral speed of the motor shaft, the propeller blades tend to unscrew and move axially outward, due to the centrifugal force and the air resistance on the blades. tor shaft increases in its peripheral speed, the balls of the governor body swing outwardly, thereby pulling upon the links and turn buckles and also pulling upon the ring plate 18, the coiled expansion springs 44 resisting the action. Under the action of the governor in this manner, the ring plate 18 is allowed to move permitting movement of the arms 42, and since thearms 42 are connected to the shanks of the propeller blades, the blades will assume a greater degree of angular pitch, according to the increased 'peripheral speed of the motor shaft, thereby When the mo- 1 increasing the pulling power of the blades,

relatively to the speed of the motor.

Should the propeller be operating 1400 revolutions per minute and assuming the air pressure on the rear surfaces of the propeller blades at 800 pounds for both blades (400 pounds each), and then assuming 400 pounds pressure in centrifugal force tendin to unlscrew the blades axially outwardly.` .the centrifugal force having been found to exert avery little force against the arms 42 on ac'- count of the comparatively sharp angles of v when the e after the airplane has ascended (all airplane motors are as a rule speeded up from 50 to 200 R. P. M., as'the' plane ascends and gains speed), the governor will then expand tending to pull the ring plate 18 from the arms and at the same time the centrifugal force becomes greater due to the increase speed tending to unscrew the blades and increase the pitch. When the ring plate 18 is pulled away froml the arms, the arms naturally follow the plate due to the force of the air against the rear surface of the blades. In case the motor ,slows down the reverse of these conditions is true and the pitch of the bladgs decreases, giving more power in a c 1m yWashers 34b are mounted upon connectors manner to the inner extremity of the shank of each blade, hence acting to draw the blade `mwardl a ainst the centrifu al force.

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While l D. Parker and ay L. Sturm are herein named as sole inventor and assignes respectively, they are named as joint 4inventors' in the application for patent on an airplane propeller iled'June 15, 1918, Serial No. 240,363, and since this present case contains claims substantially the same as those in the prior application, the present case is a continuation of' said prior application.

The invention having been set forth, what is claimed as being useful is:

-1. The combination with a propeller having blades rotatably and longitudinally movable with respect to the propeller axis, of means for automatically permitting rotation of the blades to vary their angular pitch,

and means for permitting the blades to move axially outwardly from the propeller axis simultaneously with the rotation of the blades, as the speed of the propeller increases, and means connected to the center of the hub of the propeller and connected axially to the propeller blades 'and including abutment means tending to resist said rotation of the blades to insure preventing accessive pitch changing of the blades.

2. The combination with a propeller including blades rotatably and longitudinally movable with respect to the propeller axis, of a governor controlled means for automatically permitting rotation of the blades to vary their angular pitch.

3. The combination with a propeller in'- cluding blades rotatably and longitudinally movable with respect to the propeller axis, of a governor controlled means for automatically permitting rotation of the blades to vary their angular pitch, and means for permitting outward axial movement with respect to the propeller axis simultaneously with the rotating of the blades, as the speed of the propeller increases.

4. The combination with a propeller in-I cluding blades rotatably and longitudinally movable with respect to the propeller axis, of a governor controlled means for automatica ly .permitting rotation of the blades to vary their angular pitch, said means including means to yieldably retard the rotative movements of the propeller blades.

5. The combination with a propeller including blades rotatably and longitudinally movable with respect to the propeller axis, of a governor controlled means for automatically permitting rotation of the blades to vary their angular pitch, and means for permitting outward axial movement with respect to the propeller axis simultaneously with the rotating 0f the blades, as the speed ofthe ropeller increases, said first named means including means to yieldably retard the rotative and outward axial movement of' the blades.

6. The combination with 'a propeller including blades rotatably and longitudinally movable with respect to the propeller axis, of a governor controlled means for automatically permitting rotation of the blades to vary their angular pitch, and means for permitting outward axial movement with respect to the propeller axis simultaneously with the rotation of the blades, as the speed of the propeller increases, said first named means including means to yieldably retard lthe rotative and outward axial movement of the blades, and means to regulate the yieldable mea 7. In a device for the purpose indicated, a

propeller body, a rotating shaft therefor,

propeller blades connected to the body with their" axis in' offset positions to the shaft, means connected to the center of the body and having an axially slidable connection with the propeller blades, resilient means, centrifugal means controlling the resilient means, and abutment members carried by the means which is axially joined with the dinal movement of the blades, ad means operf ated through the medium of said centrifugal force, to operate the resisting means to permit rotation of the blades tovary their angular pitch. I

In testimony whereof I hereunto affix my signature.

' WILL D. PARKER. 

